studiot

I think this is a very fair question which we need to bear in mind to keep research activity in proportion in all the different areas of Science. +1 In my opinion, for instance, the proportion of cosmology activity is overdone these days. That said, I have just been explaining brownian motion, settlemnt of suspensions and the interaction between regimes of particles of different sizes to a budding Pharmacist. So even though we need to concentrate our efforts at everyday scales, these interact with regimes operating at greater or lesser scales so we need to have some study of these as well. For the extremes, I think it's like the study of Latin. Someone should do it, but not everyone.

Methinks the member assumes too much. For your information this "came out" of Classical English.

All you have shown us is camera shot of the question. You have not even told us what method you are expected to use. You have three choices . 1) Try to follow Sensei's formula method. 2) A fully tabular method, based on reading the data from the question picture. 3) A semi graphical method again based on reading the data in the question picture. So what are your thoughts?

You are misusing both these formulae. The first one is incomplete at best. The second one contradicts what you said about the Moon. Since m is constant and c is constant mc2 is constant. If it is constant it is not different from place to place.

Hopefully a moderator will soon split off all the off topic material to where it belongs. This topic is about space.

I agree with studiot. Temperature is simply a measure of heat or energy.. Careful don't get subverted. There is more (heat) energy in the Arctic Ocean than in my little finger yet The Arctic Ocean has a considerably lower temperature (I hope perhaps I died long a go) than my little finger.

Whilst I have a certain sympathy with the comparison (underlined), I have no sympathy whatsoever with the whinge about direspect (also underlined). I seem to remember putting in a great deal of effort to produce a whole series of drawings about the properties of direction, for your express benefit. I also seem to remember that you couldn't be bothered to read them. Yet now you talk of arrogant direspect.

I hope you don't think posting as an image file let's you off accounting for what you post. I find the above quote by yourself arrogant at best and insulting at worst. That is, of course, apart from it just being plain old fashioned wrong. The theory of physical dimensions and dimensional analysis identifies a handful of fundamental quantities you need to cover the all of the equations of Physics. Mostly the triumvirate of mass, length and time are taught along with an electrical a thermal and an optical one. However it is also possible to transpose these into other sytems based on force or energy for instance. Unfortunately there is one they used to miss out and are only just beginning to teach as standard. This one cannot be substituted, but usually goes by the symbol N or n. Do you know what that is? I can certainly think of it and I am absolutely certain it cannot be transposed into any form of energy. I cannot see how you can hope to discuss more advanced Physics when you are quite wrong about some of the basics. Temperature cannot be a form of energy It is neither a measure of energy quantity nor is it energy itself. It can be defined as that which bestows direction in appropriate circumstances. The original poster here is an outstandingly knowledgeable and capable PhD candidate who has contributed much to this forum and who started this thread specifically to generate help for others in what is a very difficult subject to tie down. I find this unseemly nonsense about basics sullying and degrading for all concerned.

Exactly. Case proved.

Thank you for the encouragement. C P & C is a superb book, but I had not come across the wheel one. I must look it out. This is how Science Forums forums discussion site is meant to operate. Exchanging information.

If that is the case then that is not my idea of how discussion works so I am out of here. Good Day and Happy New Year.

Looks like homework to me. What is your course definition of 'Preload' ? To me, Preload is term used for composite materials such as reinforced concrete to allow a (slender) member to be cast elsewhere and lifted into position without sufferenign damaging transit stresses it would not encounter in service. But perhaps your course tutors have other ideas. So please provide more detail. Edit The other reason I could think of for preloading might apply to a beam that could achieve a permanent set, eg a glulam beam. Here an upward curvature would be applied to the beam, as near as calculable equal but opposite to the eventual service downward curvature so that it would end up horizontal. I have used this upward curvature to preset falsework prior to casting concrete beams in place for the same reason, though this was not due to a preloading force but a preset geometry.

I hope you realize that time is a form of energy. Matter is a form of energy. Momentum is a form of energy. Temperature is a form of energy. In fact everything you can ever think off besides space is just another form of energy. Without wishing to be rude, I think you have some serious catching up to do on basic Physics. Did you understand my comment about vector spaces? That was meant to be helpful.

No I don't require a container, the purpose is implied. Fuck it, I think the purpose is for life. But life is a whole other discussion, its probably best to keep it to physics. If the purpose is somewhere else other than the universe, where is it then? If your purpose is to convinve anyone of anything, This is about as unproductive a conversation as I could imagine.

I object to the use of the word pixel as this has a very specific meaning that implies a substrate amongst other difficulties. tile implies 2 dimensions unless you are into some very fancy mathematics. That leaves us with the general purpose cell which has done thinking humanity for centuries or longer and would, I sugges, admirably satisfy your needs without the connotation that come with the other words. Thank you for your reply. But that didn't answer my questions. Perhaps I didn't make it plain enough. Do you or do you not require a container, other than the universe itself to hold whatever purpose you describe? And no you cannot in any reasonable discussion tell me not to talk about purpose then use it yourself in the very next line. You are here facing the same problem that philosophers, throughout the history of human thought, have faced when failing to use a proper heirarchy of definitions. You are introducing undefined terms to expand your thesis, where therefore becomes meaningless. Exactly in the manner you have accused religous thinking to operate. In my opinion, this is the most difficult trap of all to avoid.

Setting aside the creation question consider this one. You have introduced the term "purpose". Is this synonymous with your earlier use of the phrase "logic behind it". My point is that either way; logic , design or purpose, this begs the questions? Is that purpose external to the universe? (How) Can the universe contain its own purpose (if it has one) ?

Energy is a property not a thing. The 'thing' theory of energy (caloric) was disproved centuries ago. Exactly so. Space on its own is a general term for the stage where stuff happens. We need to tie it down with qualifiers to properly identify which stage we are talking about. This is why, for instance, my comment used the term free space. But 'Space' could be limited to area or even a linear measurement, rather than volume. Which brings in measure. Many useful spaces (including all geometric spaces) possess a measure or distance property as mathematically defined and called a metric. Unfortunately Physics has (once again) a different definition of the word metric, but it is equally important, especially when considering Relativity questions. Back to the mathematical definiton leads us to consider those spaces without a metric. These are topological spaces and non metric topological spaces lead us directly to wormholes with the 'gluing' rules of topology. Computer programmers use another such space with packman type games on screen. To understand Space and its qualifiers we need to look into set theory, functions, mappings and containers. A good simple example of this would be to explore this view of 'vectors'; this readily shows how you need a 'container' filled with several different sets to develop useful a useful theory - that of vector spaces.

Biology, Chemistry, Engineering Physics. See if you can get hold of this book by Stephen Vogel. It might inspire you. It really does explain in layman's terms the technicalities of how Nature and Human (engineering) achieve similar objectives. https://www.worldofbooks.com/en-gb/books/steven-vogel/cats-paws-and-catapults-mechanical-worlds-of-nature-and-people-penguin-press-sci/GOR001203699?keyword=&gclid=EAIaIQobChMIiLuCp7LM3wIVA7DtCh0GCQGQEAQYASABEgI1kPD_BwE

I think that simply saying space is volume merely replaces one word with another. You could equally ask "What is volume?" In fact space is not just any old volume, it is a particular sort of volume. So to say something more useful than "space is volume you" have to detail its particulars. Furthermore that particular volume does indeed interact with energy (in the form of EM waves since there is no such thing as 'pure energy') as evidenced by the easily measurable complex impedance of free space, usually denoted by the symbol Zo.

Oops you are right. I didn't read it properly and missed the bit where you said both were off to begin with. So the smiley was to say "yup that's one way to do it." Let that be a lesson to those who are still condemned to take exams. Read the Frigging Question. My apologies. +1

"increase in pressure" - Which is exactly what I said. Neither you , nor I nor Tim Robbins have ever been anywhere near the conditions pertaining near a hydrothermal vent. I agree if we were ever subject to such conditions, the above might well happen. But this thread is concerned with living organisms that live under such conditions. Thus they do not change from our conditions to theirs as we would have to. Your scenario is predicated upon a sudden change from our normal to hydrothermal normal. I do not know what would happen if they were subject to conditions normal for us. Do you? I am just suggesting that investigating such questions might bring profitable answers.

That only works if you specify more information at the beginning.

That gentlemen is the paradox of life. Thermodynamics drives towards the reduction of energy density and energy differences. It drives towards spreading energy out further and further. Life needs to increase that density, gathering energy together. The more complicated the life the greater the need.

Surely that should be an if not a when? In my limited understanding of cell biomechancis, the membrane already resistits positve pressure within the cell over the surroundings. So the water would not initially expand, it would simply put the water under greater pressure, until it ruptured due to overpressure. So perhaps those organisms that iNow mentioned have stronger cell membranes? It is increase in pressure, not volume expansion instead of pressure increase that causes rupture of cells and steam boilers. I suppose the organism could even have a mechanism for 'letting off steam', just like a boiler.